In recent years, network printers have become remarkably widespread. Network printers receive print data from a client computer via a network such as a LAN and print an image based on the received print data.
Furthermore, a technique using a plurality of network printers to reduce a print time is known. For example, as a method of reducing a print time when printing many copies of documents, a technique referred to as tandem printing is known. According to the tandem printing technique, a print server divides copies of print documents between a plurality of network printers, so that each of the network printers prints the divided copies of print documents.